I am assuming these are winter hardy daffodils rather than the more tender type intended for indoor forcing. The best time to plant them is normally as soon as possible in the fall. But with frozen ground you have several options. One is to try to store them and wait for the ground to thaw; keep them dark, very dry and cool butt definitely not frozen. The other is to plant them in pots and set the pots in either a sunny cool (say 40 degrees) but not freezing location until spring when they can finally be planted in the ground, or finally, set the pots outdoors in a very sheltered location (a coldframe would be perfect) and sunk to the rim and somewhat covered by a surrounding insulating blanket of mulch, leaves, or sawdust. (If you do this, you might wish to take precautions against rodents by either using a commercial repellant or making a cage out of wire mesh.) Good luck with your bulbs -- what a lovely gift!